JavaScript:单击事件上对象的值

Question

我正在编写一个 codecademy.com 类(class)，教我如何使用 jQuery 构建条形图。最后一组指令是将点击事件添加到 $bar 以显示它的值。解释

Anonymous functions go like this: function(arg) { code }. In this case, a .click handler will have e, the click event, as its argument, so your implementation should have function(e) { alert code } within the .click().

这是我应该修改的函数

// Exercise 5
function addBarClickEvent($bar,value) {
    // add a click event to the bar that 
    // pops up an alert with the bars value
    $bar.click(
        // your code goes here!

        }
    );
}

我尝试了下面显示的两种解决方案，但均无效。不幸的是，该类(class)没有提供解决方案。谁能帮忙。

// Exercise 5
    function addBarClickEvent($bar,value) {
        // add a click event to the bar that 
        // pops up an alert with the bars value
        $bar.click(
            // your code goes here!
              alert($bar.value)       //my attempt
              alert(e.value)          //my second attempt
            }
        );
    }

我收到此错误消息

Make sure to define the argument to .click as an anonymous function that displays the alert.

Answer 1

假设你要显示的值是绑定(bind)时传入的值

function addBarClickEvent($bar,value) {
    // add a click event to the bar that 
    // pops up an alert with the bars value
    $bar.click(function(){
       alert(value);
    });
}

如果不是——

$bar.click(function(){
   // get value somehow
  //$(this).data('some-value');
});